Core B (Biostatistics and Data Management Core): Project Summary/Abstract Core B which has supported the PPG for >25 years, consists of a Core Leader (Lavori), a Core Physician leader (Lowsky), two Biostatisticians (Narasimhan and Tamaresis), and a Clinical Research Coordinator (Elder) who (in addition to her PPG work), supervises six Clinical Research Assistants who are supported by Stanford University Medical Center and other grants which provide services as needed to support the PPG aims. The leader of Core B and the two biostatisticians have decades of experience in medical research and, in particular, clinical trial design and data management work (organization, planning, management, monitoring and analysis) in collaboration with medical investigators, including many years of collective experience working with the BMT investigators. The Core B physician leader, Dr. Lowsky, has extensive experience in the development, conduct, data collection and analysis, study completion and monitoring of single center and multi-center clinical trials. The Core supports the clinical and preclinical projects and Core C in the proposal by leveraging the depth of expertise in analytics at Stanford University to assist project investigators in all aspects of their studies. Core B meets weekly to review and plan work, often joined by other key PPG personnel. The Core staff meet on a monthly basis with all clinical research assistants, the program project PI and the other clinical investigators, to resolve difficulties and problems, for example, in data collection, data flow, definitions, forms design and protocol development. Frequent ad hoc meetings between investigators and Core B members are scheduled, as needed. Each of the 5 new projects in the program project (on the basis of past experience and preparation of plans for the coming years to be supported through this program) will use about the same fraction of Core B effort (15% each) and the remainder is split between Core C (25%). The Core has 5 specific aims: 1) provide biostatistics consultation to the PPG project investigators for animal studies and clinical trials, 2) develop analytics for the TCR sequencing and immune monitoring assays generated by the massively parallel sequencing technologies deployed by Core C, 3) maintain the integrity of the data generated by the projects, 4) analyze data for scientific reports and annual IND and DSMC submissions, and 5) maintain the extensive BMT database. Core B is committed to active and continued participation in the PPG to help ensure that project Aims are fulfilled in the most scientifically meaningful manner.